Helicobacter pylori CagA: a critical destroyer of the gastric epithelial barrier.

The destruction of the integrity of the gastric epithelial barrier underlies the pathology of many gastric diseases, including gastric tumors. The Helicobacter pylori virulence factor CagA is one of the main destroyers of the gastric epithelial barrier. There are differences among CagA proteins that originate from different isolates. CagA translocated into the gastric epithelial cells causes significant changes in cell signaling pathways in phosphorylation-dependent and phosphorylation-independent manners, leading to cell morphological changes and host cell epithelial barrier injury, which lay the foundation for the occurrence of related diseases. As a newly identified pathogenic mechanism of CagA, miRNA is involved in the remodeling of the gastric epithelial barrier. Both the eradication of H. pylori infection and interventions against CagA-induced gastric epithelial barrier lesions may contribute to the prevention of the development of gastric tumors.